The present invention relates generally to a system for utility metering electrical usage by plug-in electric vehicles during recharging and more particularly to a mobile system for plug-in electric vehicles that allows utility metering of electricity independent of location.
Due to rising cost of petroleum and the fuels derived from it, the desire to improve efficiency to reduce air pollutants and increasingly more restrictive regulatory requirements, the automotive industry has developed new types of vehicles that utilize a combination of power sources to provide the necessary energy for the propulsion of vehicles. Rather than rely solely on an internal combustion engine, these new vehicles, referred to as hybrid vehicles, utilize an internal combustion engine in combination with an electric motor. Another version called a plug-in electric vehicle may also supplement the charging of the batteries from the electric grid or other sources. Depending on the mode of operation, the vehicle will use the combustion engine, the electric motor, or a combination thereof. By using the electric motor at various times, the combustion engine could be shut off, reducing the amount of gasoline or other fuel consumed using electricity to power the motor instead. The electric motor is powered by batteries that are periodically recharged through a combination of a generator coupled to the combustion engine, regenerative breaking technology and from the local utility grid or other external source of electricity. Regenerative breaking allows the capture of energy that would otherwise be dissipated through heat when the vehicle is slowed down or brought to a stop.
Plug-in electric vehicles provided many advantages over internal combustion engine vehicles and previous generations of all-electric vehicles. The plug-in electric vehicle provides greater range and more flexibility for the operator. Since the all-electric vehicle needed to be charged periodically, and required several hours at a minimum to recharge, the operator needed to remain aware of the level of charge remaining in the batteries to ensure they were able to return to their charging station. Plug-in electric vehicles, in contrast, by having two different sources of propulsion do not carry the same risks due to the wide availability of fuels such as gasoline.
A typical plug-in electric vehicle uses a nickel metal hydride battery or the like to store electrical charge. When run in pure electric mode, the plug-in electric vehicle can only operate for short distances, 2 km-32 km for example, before requiring the use of the gasoline engine. Since the gasoline engine recharges the batteries, at least in part, the vehicle manufacturers need to balance the amount of battery storage against fuel efficiency to provide a vehicle that meets the consumer's performance expectations.
The plug-in electric vehicles include a receptacle that connects the batteries to a standard 110V or 220V household electrical outlet and allows the consumer to recharge the batteries using utility electric power rather than by burning gasoline or other fuel in a combustion engine. This allows the plug-in electric vehicles to have a longer range in electric mode of operation since larger capacity batteries may be used, resulting in vehicle that uses less gasoline and thus lower emissions.
Incentives, such as lower electrical tariff rates for example, exist to encourage greater usage of utility electrical power over gasoline combustion. However, it is difficult to provide these benefits to the operator when the vehicle is charged away from their home or place of business since the operator's meter and utility account is associated with a physical location.
Thus, while existing metering systems are suitable for their intended purpose, there remains a need for improvements, particularly regarding the metering of plug-in electric vehicles and the interfacing with a utility.